Landmines are area denial weapons and are intended to slow, re-direct or obstruct the mobility of military forces. The landmine threat usually continues long after the conflict ends, posing great risk to the civilian population. Since World War II, handheld landmine detection has been based on the metal detector. Unlike older metal-cased landmines, today's modern anti-tank and anti-personnel mines are made primarily of plastic and have very little metal content. Landmines by their very nature are laid in areas of conflict, and the surrounding soil typically contains high levels of metal clutter, e.g., shrapnel and metal shell casings. This clutter significantly increases the difficulty of finding modern mines using only a metal detector.